Lead accumulator



April 1923 EIM LEAD ACCUMULATOR Filed April 1 1925 2 sheets-s 1 I i 2:; ii

Q 14 h E r L E: m

my 5 f 0 R sis life of the accumu ator is thus increased.

Patented Apr. 24, 1928.

I UNITED "STATES. PATENT OFFICE.

mum on, or uvmors-manr, rmcn, asszenon r seem! monm LI GABBONE, OF LEVALLOIS-PEBRET,

mm accuum'ron.

Application filed April is, 1925, Serial m. 24,235, and in France Jane 14, 19:4.

Thepresent invention has for object an improvement in .the manufacture of lead accumulators and havin as an object to reduce their weight and increase their mass ca acity.

his. improvement consists, substantially, in the use, as an active material in the accumulator, of a mlxture composed .of lead, or of a lead oxide, in the form of 10 powder, and of a orous conductin body in anular form, 0 small denslty, aving a igh power of absorption for gases and rendered, by suitable treatment, lmpervlous to liquids whilst remaining permeable to gases,

- so as to preserve, in the course of the operation of the accumulator, its power of absor tion for gases.

y the present invention the active material roper (lead or lead oxide in powder form is intermixed with a material taking an active part itself in the operatlon of the accumulator.

By way of example, the product in accordance with the present invention and ada ted to be used as an active material in a and accumulator, may have the following coin pos1tion:

1. Powder of very porous charcoal, in gage grains of about 0 m/m 5 to 1 m/m,

2. Powder of very porous charcoal in extremely fine grains passing through a screen gigging-150 to 200 meshes per linear inch,

3. Pulverized lead or lead in powder form, 60%.

Instead of lead, oxides of lead can also be used, particularly peroxide of lead or litharge.

I The granular or-powdered orous charcoal having grain sizes as in t e above example, may be rendered impermeable to liquids {that is unwetted by liquids) yet permeable to gases in the following manner.

In fact, the particles of the porous ima The granular or powdered absorbent mapervious body, mixed with the active mate- 2 rial, absorb upon charging the accumulator,

' oxy n and hydrogen WhlCh have not been fixe by the lead and, by the lead oxide, and restitute these gases upon discharge.

Moreover. owing to the absor tion of oxy en by the porous im ervious bo y mixed wit% the active materia, the action of sulphuric acidon the lead is slower. As a result the sulphatation, that is, conversion of lead into lead sul hate is inhibited. The

On the other hand the said porous body containing lead or lead oxide intimately mixed, increases the surface of contact of the latter with the electrolyte.

In an accumulator'constructed in accordance with the present invention, the porous conductin im ervious ains or particles, mixed wit lea or with ead oxide therefore have a double function:

1. The subdivide the active material proper, t at is, the lead or lead oxlde and thus increase its efiective surface area.

2. They act to prevent sulphatation of the lead and to absorb oxygen and hydrogen liberated during charging.

Owing to the lightness of these porous oonductmg impervious rains and to the state of subdivision of t eactive material,

the mass capacity of the accumulator is u considerablymcreased.

- ized lead or with a lead oxide in powder terial is exposed for. a suflicient length of time in a vessel containing vapours 0 fatty bodies, or of vapours of hydrocarbons, or of vapours of paraflin; or the absorbent material is moistened with a solution of parafiin in benzine and the benzine'is subsequently evaporated. These grains can also be mixed with a solution of rubber in gasolene and the gasolene subsequently evaporated.

The absorbent material thus rendered imermeable to liquids is mixed with pulverform, for instance in the following proporion:

Pulverized lead or lead oxide in powder form, 80%.

Treated porous grains, 20%.

The'mixture is moistened with a solution of sulphuric acid, of 10% strength for, instance.

The invention. is moreover characterized by the application of the active material as above defined to various modes of construc-: tion of accumulators.

Figs. 1 to 3 illustrate in 'vertical section three different modes of applications. I Fi 4. and 5 illustrate another mode of 'apphcation, Fig. 4 is a vertical cross section of the accumulator; Fig. 5 illustrates in elevation one of the plates of the latter.

Figs. 6 to 9 illustrate a mode of construction of accumulator plates utilizing the asno tive material above defined'and on which i 'wood fibre or any other materi-a used as diaphragm in accumulators. 'The positive electrode e and negative electrode 7, each constituted by a lead strip or blade, are horizontally arranged and respectively placed in the two compartments 6, 0. These latter are filled with the active material the composition of which has been given'above.

On the whole thus constituted is poured sulphuric acid of 10 or 15 B.

In the form of construction illustrated in Fig. 2, the porous partition d is vertical and the two electrodes 6, f, constituted by. lead strips or rods, are vertically arranged.

Fig. 3 shows another method of construction in which the two anodic and cathodic compartments are constituted by two parchment bladders b 0 extending into the vessel (1; these bladders respectively contain the two electrodes 6, f and are each filled with the active material above defined, moistened with a solution of sulphuric acid of about 15 B. The vessel a is, moreover, filled with a solution of sulphuric acid also of 15 B.

Figs. 4 and 5 illustrate a modification in which use is made of two plates made of retort carbon perforated with holes or of ordinary lead grids. e and desi nate two plates thus constituted, per orate for instance, with circular holes 6 and c. In these holes, are compressed with a spatula, or otherwise, small slugs formed by the active .mixture above described, moistened in the proportion of 10% of the weight of dry mixture with a solution of sulphuric acid of 10% strength. These two plates forming the anode and cathode are lmmersed in a solution of sulphuric acid of about 10% stren h contained in a vessel which is not attac ed by the acid.

An accumulator plate can also be constructed in accordance. with the present invention by operating in the following manner:

An intimate mixture is formed by means of the following ingredients:

2 kgs. of litharge in powder form. I

0 kg. 200 of charcoal in grains of 0 m/m. 5 to 1 m/m.

0 kg. 200 of charcoal in the form of an extremely fine wder.

. 0 kg- 200 of melted glucose.

Then the plate bemg placed in a foundry mould, of suitable shape, molten lead is cast in the grooves 72. of this plate. When 0001- ing, this lead constitutes a grid tin intimate contact through all its points with the plate 9 (Figs. 8 and 9).

Instead ofv the mixture indicated above, the following mixture can also be used:

2 kgs. of litharge in powder form.

0 kg. 400 of charcoal in grains of 0 m/m. 5 to 1 m/m.

0 kg. 200 of melted glucose.

As previously stated, this mixture is moulded in the shape of a plate, and the plate obtained isheated to a temperature of about 400 0., but, in this case, before casting of the lead, the plate is impermeabilized and, for that purpose, is exposed, as above mentioned, to the action of vapours of hydrocarbons or of paraflin.

The active material can be simultaneously agglomerated and impermeabilized by using as binding means a solution of rubber; in this case, one operates in the following manner: 7 p I A mixture is prepared by means of 0 kg. 400 of charcoa in grains of 0 m/m. 5 to' 1 m/m. and of 0 kg. 200 of a solution of rubber containing about 0 kg. 100 of rubber per litre of gasolene.

On the other hand, 2'kgs. of litharge or of red lead in powder form are moistened with 200 cubic centimetres of a solution of sulphuric acid of approximately 10% strength.

The whole is then mixed together.

The paste thus obtained is compressed into the desired shape, the plates thus formed are finally placed in a stove and heated for instance to a temperature of 100 C. during the time necessary for completely evaporating the gasolene and water.

trong resistant and resilient, accumulator lates are thus obtained and from this fact t ese lates do not risk being disintegrated at igh rates of charging and discharging. Y

"Moreover, the rubber thus incorporated has the property of absorbing for its own part the gases. of the reaction upon chargm and of restituting them u on discharge.

t is to be understood that t e proportions given above are indicated by way of examples 012; and that they can be modified.

The In es of execution above described are given by way of example only; the shape, dimensions, details, of construction of the constituent elements of the accumulator and the number of anodic and cathodic compartments can be varied according to the applications.

Claimszv 1. An electrode element for lead accumulators comprising an intimate mixture of powdered electrode material and a finely divided porous material rendered impermeable to liquids but having a high absorption power for gases.

2; An electrode element for lead accumulators comprising an intimate mixture of powdered electrode material and a finely divided absorbent charcoal rendered impermeable to liquids but'having a high absorption power for gases.

3. An electrode element for lead accumulatbrs comprising electrode material intimately mixed with absorbent charcoal of large grain size and finely powdered absorbent charcoal, said absorbent charcoal being rendered impermeable to liquids but having high absorption power for gases.

4. An electrode element for lead accumulators comprising lead electrode material intimately mixed with absorbent charcoal of lar e grain size and finely powdered absor entcharcoal said absorbent charcoal being rendered impermeable to liquids but having high absorption power for gases.

5. An electrode element for lead accumulators comprising electrode material intimately' mixed with absorbent charcoal oi large grain size and finely powdered absorbeni; charcoal, said absorbent charcoal having a film of rubber thereon to render it impermeable to liquids but having high ab sorption power for gases.

6. The process of preparing an electrode element for lead accumulators which comprises treating absorbent charcoal to render the same impermeable to liquids but permeable to gases and thereafter intimately mixing the so treated charcoal with lead electrode material in finely divided form.

7. The process of preparing an electrode material for lead accumulators which comprises treating absorbent charcoal with a rubber solution to render said charcoal impermeable to liquids but permeable to gases and thereafter intimately mixing the so treated charcoal with finely divided lead electrode material,

The foregoing specification of my lead accumulator signed by me this 9nd day or April, 1925.

RENE UPPENHETM. 

